I needed a light small unit that was easy to travel with I am more than happy with my set up its the tiny Manfrotto 785B but with a Slik AF1100E pistol ball mount total weight just over 1KG and it even fits on the side on my camera bag.
I dont use it with the legs splayed as with my D7000 and a 18-200VR on it its a bit much for the very thin legs but in normal config I have used my 50-500 bigma with no problems. The reason I changed the head from the normal one is the Slik is more robust and has a pan only plate that is almost as smooth as a fluid unit so its great for Video work.
I havent wasted the original head though, it's now fitted on my walking pole and makes a great hiking monopod.